NVME-IO-PASSTHRU(1) NVMe Manual NVME-IO-PASSTHRU(1) NAME nvme-io-passthru - Submit an arbitrary io command, return results SYNOPSIS nvme [] io-passthru [--opcode= | -O ] [--flags= | -f ] [-rsvd= | -R ] [--namespace-id= | -n ] [--cdw2= | -2 ] [--cdw3= | -3 ] [--cdw10= | -4 ] [--cdw11= | -5 ] [--cdw12= | -6 ] [--cdw13= | -7 ] [--cdw14= | -8 ] [--cdw15= | -9 ] [--data-len= | -l ] [--metadata-len= | -m ] [--read | -r] [--write | -w] [--input-file= | -i ] [--metadata= | -M ] [--show-command | -s] [--dry-run | -d] [--raw-binary | -b] [--prefill= | -p ] [--latency | -T] DESCRIPTION Submits an arbitrary NVMe IO command and returns the applicable results. This may be the simply the command's result and status, or may also include a buffer if the command returns one. This command does no interpretation of the opcodes or options. The parameter is mandatory and may be either the NVMe character device (ex: /dev/nvme0), or a namespace block device (ex: /dev/nvme0n1). On success, the returned structure (if applicable) may be returned in one of several ways depending on the option flags; the structure may printed by the program as a hex dump, or may be returned as a raw buffer printed to stdout for another program to parse. OPTIONS -O , --opcode= The NVMe opcode to send to the device in the command Required argument as this param is mandatory. -f , --flags= The NVMe command flags to send to the device in the command -R , --rsvd= The value for the reserved field in the command. -n , --namespace-id= The value for the ns-id in the command. Defaults to 0. -[2-9] , --cdw[2-3,10-15]= Specifies the command dword value for that specified entry in the command -r, --read, -w, --write Used for the data-direction for the command and required for commands sending/receiving data. Don't use both read and write at the same time. -i , --input-file= If the command is a data-out (write) command, use this file to fill the buffer sent to the device. If no file is given, assumed to use STDIN. If the command is a data-in (read) command, the data returned from the device will be saved here. -M , --metadata= If the command is a data-out (write) command, use this file to fill the metadata buffer sent to the device. If no file is given, assumed to use STDIN. If the command is a data-in (read) command, the metadata returned from the device will be saved here. -l , --data-len= The data length for the buffer used for this command. -m , --metadata-len= The metadata length for the buffer used for this command. -s, --show-cmd Print out the command to be sent. -d, --dry-run Do not actually send the command. If want to use --dry-run option, --show-cmd option must be set. Otherwise --dry-run option will be ignored. -b, --raw-binary Print the raw returned buffer to stdout if the command returns data or a structure. -p , --prefill Prefill the buffer with a predetermined byte value. Defaults to 0. This may be useful if the data you are writing is shorter than the required buffer, and you need to pad it with a known value. It may also be useful if you need to confirm if a device is overwriting a buffer on a data-in command. -T, --latency Print out the latency the IOCTL took (in us). GLOBAL OPTIONS The following options are defined at the top-level nvme command and are available to this subcommand: --dry-run Print the command that would be executed, but do not actually execute it. --no-ioctl-probing Disable probing for 64-bit IOCTL support. --no-retries Disable retry logic on transient errors. -o , --output-format= Set the reporting format to normal, tabular, 'json, or binary. Only one output format may be used at a time. --output-format-version= Select the output format version. Version 1 uses the original field naming, while version 2 (default) provides more consistent and script-friendly field names. --timeout= Set the timeout for the command in milliseconds. -v, --verbose Increase the level of detail in the output. May be specified multiple times to further increase verbosity. These options can also be set as machine-wide defaults in nvme-cli.conf(5). A command-line flag always overrides the file. EXAMPLES nvme io-passthru /dev/nvme0n1 --opcode=2 --namespace-id=1 --data-len=4096 --read --cdw10=0 --cdw11=0 --cdw12=0x70000 --raw-binary NVME Part of the nvme-user suite NVMe 09/18/2026 NVME-IO-PASSTHRU(1)